Tip dresser

Abstract

A rotary cutter includes a pair of recessed receivers which receive the respective tip ends of a pair of electrode tips, and a through portion which runs through in a rotation axis direction and provides an opening that communicates with each of the recessed receivers. A cover case covers the lower recessed receiver of the rotary cutter and has a notch which is associated with the lower recessed receiver. Over the upper recessed receiver of the rotary cutter, a cover plate is fixed to cover the upper recessed receiver. An electrode tip insertion hole is cut through a center portion of the cover plate.

What is claimed is: 
     
       1. A tip dresser comprising:
 a rotary cutter configured to simultaneously cut respective tip ends of a pair of spot-welding electrode tips, arranged to face each other on both sides in its rotation axis direction, by rotating a pair of cutting edges which are provided for the respective tip ends; and 
 a cover case configured to prevent chips shaved off by cutting work with the rotary cutter from scattering, wherein 
 the rotary cutter includes: 
 a pair of recessed receivers arranged symmetrically in the rotation axis direction to receive the respective tip ends of the electrode tips so that the center axis of the electrode tips agrees with the rotation axis while the receivers are cutting the respective tip ends of the electrode tips; and 
 a through portion running in the rotation axis direction to provide an opening that communicates with the respective recessed receivers, 
 the cover case is provided to cover one side of the rotary cutter that has one of the pair of recessed receivers, and has an opening associated with the one recessed receiver, 
 a cover plate having, at its center portion, an electrode tip insertion hole, of which the shape corresponds to the profile of the electrode tips, is fixed to the other side of the rotary cutter that has the other recessed receiver so as to cover the other recessed receiver, 
 an air discharge means for discharging compressed air toward a surface of the cover plate is arranged close to the other side of the cover plate opposite from the rotary cutter, and 
 a plurality of air inlet holes are cut side by side through the cover plate at such positions as to face the cutting edge in a direction in which the rotary cutter rotates. 
 
     
     
       2. The tip dresser of  claim 1 , wherein
 the air inlet holes form slits which extend radially from the rotation axis of the rotary cutter. 
 
     
     
       3. The tip dresser of  claim 1 , wherein
 an air sucking means for sucking air from inside the cover case and a compressed air introducing means for introducing compressed air into the cover case are connected to the cover case, the compressed air introducing means and the air sucking means being spaced apart from each other so that the rotation axis of the rotary cutter is located between these two means. 
 
     
     
       4. The tip dresser of  claim 1 , wherein
 an air sucking means for sucking air from inside the cover case and a compressed air introducing means for introducing compressed air into the cover case are connected to the cover case, the compressed air introducing means and the air sucking means being spaced apart from each other so that the rotation axis of the rotary cutter is located between these two means. 
 
     
     
       5. The tip dresser of  claim 2 , wherein
 an air sucking means for sucking air from inside the cover case and a compressed air introducing means for introducing compressed air into the cover case are connected to the cover case, the compressed air introducing means and the air sucking means being spaced apart from each other so that the rotation axis of the rotary cutter is located between these two means.